Children who enter puberty early have the strongest bones as adults, a study has shown.
Scientists at the University of Bristol studied thousands of British children, taking bone scans over the course of 15 years. They found the later a child hit puberty - defined as the later they had their growth spurt - the weaker their bones were.
Growth in bone strength starts to halt in the early twenties, therefore those who hit puberty late still had weaker bones into their adult life. This can be a crucial factor for whether an adult goes on to develop conditions such as osteoporosis later in life, experts said.
Researchers collected data on 6,389 children who had bone scans between 10 and 25 as part of the Children of the 90s Study. They calculated the age a child hit puberty by looking at when they had their largest growth-spurt - called 'age at peak height velocity'.
Children who hit puberty earliest - before 10.5 years in girls and before 12.5 years in boys - had 12 per cent more bone strength during puberty than those who hit it later - from 12.7 years in girls and 14.5 years in boys.
Although teens who had their pubertal growth spurt later than their peers had lower bone-strength, they did 'catch-up' to some degree. By the time they were 18, their bones had acquired density at a much quicker speed. Particularly, boys had a more intense growth. But it wasn't quite enough – by age 25 those who hit puberty later still had almost five per cent less bone strength than early maturers.
Puberty is a key life milestone when teenagers go through a growth in their skeletal system, among other things.
The greatest gain in bone size and strength occurs during adolescence because of hormones.
But bones keep growing in strength well after puberty, reaching their maximum strength - called 'peak bone mass' - in the early 20s.
Peak bone mass at the end of teenage growth spurts is thought to be an indication of later risk of fractures and osteoporosis.
The study, considered to be the first of its kind, was published in the Journal of the American Medical Association's Network Open.
